I realize this is a "toy," and toys are generally thought to be for kids.
This misconception causes and undervaluing of toys, and of play, and unfortunately deludes the marketplace.
It manifests here in the fact that these fellows turn off after 4 minutes, so if you want them to stay on and run across your desktop, you must turn them back on every four minutes. I have 6 cubes total, and do plan to purchase more, so that is 6 button presses every four minutes. Multiply that by however many groups of four minutes there are in an hour, or however long you want them on, and it becomes a lot of button pressing. I miss a simple on/off function.
There are other things that could be included in these units, things adults would be interested in, and kids probably would enjoy as well, things like artificial intelligence, so their behavior is more human-like and less predictable, and memory, so that they don't start from scratch every time they're turned on.
For what these "toys" cost, and how far technology has come, they should do more. These are a great idea, but if they are to survive, they really MUST do more than just be cute and entertaining for four-minute segments.
For their price, they must do more, or their cost must be reduced.
Since I was asked about the educational value, I also wonder what children are taught by the fact that these cube men are all just that, men. There are no women, and they are also clearly not "genderless". They are clearly men, and they are at times violent (!).
Obviously kids aren't going to think everyone in the world is completely male, since they can see otherwise, but they may think violence is an amiable means to interact with your friends. It's not.
Draw your own conclusions. Children are inundate daily with our gender stereotypes, and the only way that can change is if we make it change.
Notice I've still given these items a high score. I like them, despite the problems above, and I would like nothing more than to see them usher in a new era for intelligent toys. It's time for manufacturers to stop being lazy. We require something more entertaining as adults, and for our kids, we should settle for nothing less than intelligent, conscious entertainment.
As for the durability, I can't comment. They seem quite solid to me, but I'm gentle, and I'm not going to toss one around to see if they break. They're rather overpriced for that.